Connect Flutter application to DynamoDb database

You need to know about these services, before connecting your flutter app

1. Api Gateway - Service used to create a Rest API, which links the flutter app to cloud.

2. Lambda - This service sits in the middle, connecting the Api to your database ( DynamoDB ). Basically a function, it also states how the data is collected.

Try these tutorial

https://medium.com/avmconsulting-blog/how-to-build-a-serverless-api-with-dynamodb-aws-lambda-and-api-gateway-d61ac63c27dd

It is actually pretty easy.

1. First add this package to your project.

2. Then create your models you want to read and write. Along with conversion methods.

class Parent {
   String name;
   late List<Child> children;

 
  factory Parrent.fromDBValue(Map<String, AttributeValue> dbValue) {
    name = dbValue["name"]!.s!;
    children = dbValue["children"]!.l!.map((e) =>Child.fromDB(e)).toList();
  }


  Map<String, AttributeValue> toDBValue() {
    Map<String, AttributeValue> dbMap = Map();
    dbMap["name"] = AttributeValue(s: name);
    dbMap["children"] = AttributeValue(
        l: children.map((e) => AttributeValue(m: e.toDBValue())).toList());
    return dbMap;
  }
}

(AttributeValue comes from the package)

Then you can consume dynamo db api as per normal.

3. Create Dynamo service

class DynamoService {
  final service = DynamoDB(
      region: 'af-south-1',
      credentials: AwsClientCredentials(
          accessKey: "someAccessKey",
          secretKey: "somesecretkey"));

  Future<List<Map<String, AttributeValue>>?> getAll(
      {required String tableName}) async {
    var reslut = await service.scan(tableName: tableName);
    return reslut.items;
  }

  Future insertNewItem(Map<String, AttributeValue> dbData, String tableName) async {
    service.putItem(item: dbData, tableName: tableName);
  }
}

Then you can convert when getting all data from dynamo.

List<Parent> getAllParents() {
   List<Map<String, AttributeValue>>? parents =
        await dynamoService.getAll(tableName: "parents");
  return parents!.map((e) =>Parent.fromDbValue(e)).toList()
}

You can check all Dynamo operations from here